Vershd.io - Vershd is a fluent git GUI software designed for professional software engineers who are beginner and intermediate users of Git.
TortoiseSVN - The coolest interface to (Sub)version control
Assembla - Integrated, on-demand tools to build software faster, with less stress. Get started for free and find out why over 800,000 users trust Assembla.
SmartSVN - SmartSVN is a graphical client for the Open Source version control system Subversion (SVN).
Xversion - Super easy enterprise class version control.
SourceTree - Mac and Windows client for Mercurial and Git.